Canon 70D: How Good is the Cutting-Edge Autofocus System While Shooting Video?

After many years of releasing similar cameras with small changes, Canon has finally unleashed a brand new technology inside the new 70D they are calling Dual Pixel CMOS AF. The major breakthrough with this technology is that it should give excellent autofocus whether you're in stills mode or in video mode. Now, you might be thinking you'd never want or need anything like that, but Johnnie Behiri over at cinema5D took the 70D for a spin to test not only the video quality, but how good the autofocus actually is. Check those videos out below.

You can work with the autofocus engaged in 2 ways. with or without touchscreen.
If you choose working with the touchscreen you might get more accurate and easy to “change focus” results but in my case, this option is useless when shooting outside as I can not judge the right exposure in full daylight when looking at the LCD screen.
The other option is to disable the touchscreen and work with the back wheel. That’s the method I used when shooting this video as I had a Zacuto VF attached to the camera.
Also note that if you like working with an external monitor, the LCD screen will go blank right after attaching the HDMI cable.

The autofocus does a pretty good job, much better than I expected in certain shots. Again, this may or may not be something you trust for specific jobs or purposes, but it seems to work well enough for the most part, especially if you were handing this camera off to someone to take BTS footage in a darker environment and you need the high-ISO capabilities of a DSLR but the person shooting is having a harder time keeping focus.

I think one of the best ways this could be used without too much trouble is a steadicam type shot. If you've only got one subject in the frame and it's tracking the person's face, it should work pretty well, and it's unlikely to go hunting anywhere else as long as you've got the one person as the major subject in the frame.

So while it seems like the actual video quality of the 70D isn't much different from any of their current APS-C DSLRs, the major improvement is in the sensor tech related to the autofocus. We will likely see this development in future Canon cameras, so I would expect the next 7D to have better video and include this new Dual Pixel CMOS AF.

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16 Comments

I wrote this on the comment section on vimeo, might be some help for those that can see how some other brands are at least innovating

Hi Johnnie, thanks for the independent test. It is hard to get proper testers these days, that are not bias to certain brand.
I would invite you to test an aps-c dslr that has no moire/aliasing problem, about the same high resolution video than the gh2, very good low light which is close to the 5dmark3 and has about 12 stop of DR. More so that you have clean uncompressed hdmi output in a weather sealed body for $ 1200.

It is really sad that no known reviewer has taken a little time to test this camera which is the Nikon D7100. When I see all these people that are going through disappointment after disappointment with the Canon dslr, when you have other brands that are at least innovating and no one reviewing these brands, it is a pity. This comes from someone who as Nikon shooter bought a Canon 7D because Nikon was no good in video during those days.

You can see some test I did below
Sharpness test against the panasonic gh2, It is a blind test and as you can see it is so close that no one really knew which is which
dvxuser.com/V6/showthread.php?310503-Nikon-D7100-vs-Panasonic-gh2-sharpness
A DR test with my light meter with different picture profile
dvxuser.com/V6/showthread.php?311058-Nikon-D7100-12-13-Dynamic-range-test

I've not had a chance to play with the D7100, but focus hunting on the D7000 in video mode was horrible, and my D600 isn't much better. Image quality for a DSLR is amazing, but I still have to rely on manual for video.

Saying that, I believe the D7100 shares heavily from the pro-grade autofocus of the D300, rather than the prosumer grade D7000, so your camera should have spectacular autofocus. As a Nikon shooter, I'd love for people to start taking Nikon more seriously for video, so there'd be more info out there to draw upon.

Autofocus seems to work great, esp. because it looks to give good results without "hunting" Although, my guess is it will only work this well with STM lenses which, if I'm not mistaken there is only the 40mm pancake (used in the video above) and the 18-135 3.5-5.6 STM which is pretty slow (referring to aperture not focus speed).

Great tech, but nothing to get excited about just yet until the lenses catch up, unless it works just as well with the USM lenses. -any word on this?

I prefer manual, but there are plenty of occasions where little autofocus couldn't hurt (live events, documentary, etc)

The autofocus indeed works very very well with USM lenses (non-STM). Also Sigma lenses too! I'm primarily testing it for video so I don't know how well it works for stills yet. Also I'm testing primarily indoors in low light with a cluttered recording studio moving from piece to piece at varying depths of field. Sometimes using touchscreen, sometimes just letting it hunt. It doesn't do much obvious hunting, which is great. It autofocuses and tracks very well on my 50mm 1.4, 28mm 1.8, 70-200 f2.8 IS II, 24-105L f4, so far any autofocus lens I've thrown on it. The process is a bit noisier with non-STM lenses, but nothing too crazy and certainly worth it for such a useful feature. I feel much better throwing this body in an assistant's hands for some b-roll or second camera and feeling like I'm going to get SOMETHING in focus in post. The face tracking seems to work very well too. Overall I'm very impressed with the AF.

I'm a manual focus shooter, but occasionally find myself in a wide jib shot from a tight location, or a lockoff wide shot, or quick and dirty steadicam type shots, and the autofocus would be a great assist in these cases.

The moire, however, is indeed present. Much like the rebel lines. Not as bad as the 5DmkII (which has horrible, soul-crushing moire). I also wish the 70D had the 3x video mode of the t3i, t5i. For video this is a ridiculously good feature. A 30mm 1.4 prime becomes a 90mm 1.4 prime with no moire. A 17-55 IS f2.8 becomes a 49-165 IS f2.8. So you can go from 17-165 at f2.8 with IS without changing lenses. A 70-200 f2.8 IS II becomes a 210-600 f2.8 with IS. I was hoping the 70D had this 3x feature but it doesn't out of the box. I'm also hoping Magic Lantern release a build for the 70D as they have some great features, although don't be expecting 24p 1080 RAW from it even IF Magic Lantern becomes a reality on this body, as it uses only SD cards, not CF on the 70D.

A great first camera if you have nothing, or a great 2nd camera to a 5DmkIII or a Canon C100, C300, etc.

d5200 does just as good as this camera probably at more than half the price, plus it has very minimum to no moire at all, has higher pixel count on picture side for cropping, selective color in video, and hdmi out

I have shot the 5200 and it makes very nice images indeed. Major note to Canon shooters--you can't change the f-stop on the 5200 (or any Nikons I believe) while shooting video or even while in live view mode. It's a very strange thing to me. Also the rolling shutter in the 5200 was horrendous. I tracked a person walking briskly across a room and her body warped from 12 feet away. I didn't use the autofocus on the 5200 so I can't comment on that. For outdoor wides and establishing shots, it was wonderful. No moire to speak of and very very sharp on highly detailed landscapes.

Nice job. While there are other cameras that do it well (D5200 mentioned), I have Canon lens and like that this
works with my other EOS lenses. Lens noise is a factor, but an external boom mic solved that years ago. For me it difficult to focus manually with outdoor/sunny locations, even with a hood loop. I am looking forward to trying out my 70D that is hopefully coming next week :)

how can anyone call it a review when they just make assumptions and dont do any real tests?

"I think one of the best ways this could be used without too much trouble is a steadicam type shot. If you’ve only got one subject in the frame and it’s tracking the person’s face, it should work pretty well, and it’s unlikely to go hunting anywhere else as long as you’ve got the one person as the major subject in the frame."

Ok so he has never done this and no idea of how well this works in low light...

can anyone one post a reply link with real test footage that actully shows apature tests in low light and how well the auto focus / focus tracking works? I have heard that it only works in high ASAs at f11 or more and not at all in low light.. but cant find any videos,, just these fake sponcored spots that are fake reviews just to get video hits to drive web traffic to sell ad space... is that eveyones biz now who does camera reviews, they are not really shooters and just toss anything up, tag it as a review, and sell adds on thier page..

Hi guys, anyone know whick other canon dslr, cheaper ones have same or newer af system? i know sl1 hast hybrid cmos af ii, wich is between af i and dual pixel i suppose, any other? i cant decide if buying t5i or sl1 for video

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